In the production assembly of aircraft, the majority of substructure such as fuselage frames and longerons, along with wing spars and ribs, are joined to the skin of the aircraft with thousands of fasteners. Further, a plurality of fastener types, along with variations in diameters and grip lengths, are typically used in an aircraft assembly or subassembly. (Generally, a fastener grip length refers to the cumulative thickness of the parts that the fastener holds together). Moreover, a majority of the substructure parts are manually assembled and are not assembled using automated fastening equipment.
Automated fastener delivery systems that automatically deliver fasteners to a workpiece, or a fastening device, have been employed in various ways to simplify the fastener retrieval process in various types of automated fastener installation systems. Some of these known automated fastener delivery systems involve various types of storage devices and vibratory feed bowls that utilize different types of escapements for feeding fasteners through a tube to different types of fastening devices. Such known fastener delivery systems are typically employed in high rate production environments that have relatively large assembly systems permanently installed at a fixed location within a production facility. The equipment generally comprises a storage device for the fasteners and a mechanism or system that retrieves fasteners from the storage device and transports the fasteners to the workpiece or fastening device.
In at least one known fastener delivery system fastener storage cartridges are utilized to cache the fasteners before delivery to a fastener installation device or the like with pressurized air. Typically, the fastener cartridges comprise at least one tube in which the fasteners are stacked longitudinally end to end. The fastener cartridges are filled off line either by hand are automatically. The fasteners are then removed from the various storage tubes or cartridges and delivered through a common passageway to the fastener installation tool. However, this type of known fastener delivery system requires a separate fastener escapement mechanism to remove and deliver the fasteners. Additionally, often the shape of the fasteners are not suitable for stacking end to end in the fastener storage tubes, which causes the fasteners to jam in the storage tubes. At least one known fastener delivery system has employed spacers between each fastener to prevent the fasteners from jamming. However, this consumes space within the storage tubes, thereby reducing the number of fasteners each tube/cartridge can hold. Additionally, each spacer has to be removed from the cartridge before a subsequent fastener can be removed, thereby impeding the rate at which fasteners can be delivered to the fastener device.
Accordingly, a need remains in the art for an automated fastener delivery system that is portable, includes a fastener storage system in which the fasteners do not jam, and efficiently delivers the fasteners to at least one work station or tool in a timely manner.